ICHNEUMONIDAE: : Stenomacrus Förster 1869
Diagnosis:Characteristics of Stenomacrus include: 1. Body size <10mm; 2. Position of spiracle on T1 at, close to, or before centre; 3. Shape of aerolet in forewing pentagonal (closed); 4. Colour of face variable; 5. Metasoma compressed laterally; 6. Size of ocelli small; 7. Length of antennae quite short, not exceeding past T2; 8. Length of ovipositor barely visible; 9. Wings present; 10. Colour of wings hyaline (clear); 11. Sternaulus absent; 12. Shape of face in lateral view strongly bulging ; 13. Sternite on T1 (viewed laterally) not extending past spiracle; 14. Shape of T1 (viewed laterally) evenly curved; 15. Number of teeth in mandibles 2; 16. Metasoma same colour throughout; 17. Length of T1 longer than T2; 18. Sculpture on mesoscutum finely pitted, many hairs; 19. Width of T1 (viewed dorsally) gradually widening from anterior to posterior; 20. Glymma on T1 present, (deep pit); 21. Sculpture on metasoma smooth with a semi-glossy or satin appearance at least on T2; 22. Propodeum very short (not reaching beyond coxal insertion).
Similarity to Other TaxaStenomacrus has a bulging face similar to genera of the subfamily Metopiinae ( Carria , Sciron , Hypsicera ). However, Metopiinae have a small triangular process between the antennae, and the malar space lacks a subocular groove.
Some small Aucklandella also have a 'bulging face' but these have the spiracle of T1 well behind the centre (in Stenomacrus the spiracle on T1 is at, close to, or before centre).
Distribution in NZ
South Island: MC.
Species in NZIn New Zealand, this genus is only known from one specimen and it is not considered to be established.
Biology & hostsNo information is available for New Zealand. Overseas they are widespread and common.
Sources of informationGauld ID 1984. An Introduction to the Ichneumonidae of Australia. London, British Museum (Natural History). 413 p.
CitationWard DF & Schnitzler FR. 2013. Ichneumonidae of New Zealand. Genus Stenomacrus http://ichneumonidae.landcareresearch.co.nz
Accessed: 6 July 2020